Applying APCA and Huetone for Color Accessibility of User Interfaces

Abstract

Over the 15 years since the adoption of WCAG 2.0, user interface design and interface devices have changed substantiallys. However, many interface guidelines still employ the old color contrast formula. In the last few years, the range of color accessibility tools has expanded with a variety of newcomers: LCH and HSLuv, enhanced color models adapted to human perception, have been developed; Advanced Perceptual Contrast Algorithm (APCA) has been implemented as part of WCAG 3.0; Tools for creating color palettes have been developed based on its implementation, such as Accessible Palette and Huetone. These new tools were used during a redesign of an office suite to change the color scheme. The purpose of this paper is to demonstrate practical results of using these tools. Despite the fact that WCAG 3.0 has not yet been adopted, APCA shows more accurate results for measuring color contrast. Huetone Color Tool provides capabilities of palette analysis using the LCH color space model with easy color contrast and color distance calculation.